Photolithography generally refers to an optical process used to transfer geometric patterns onto a substrate or a layer over a substrate. Many photolithography techniques use a light-sensitive material (commonly referred to as a “photoresist”) to create geometric patterns. For example, a photomask, or a reticle, may be disposed over the photoresist, which may then be exposed to a radiation beam such as ultraviolet (UV) or an excimer laser. A bake or cure operation may be performed to harden the photoresist, and a developer may be used to remove either the exposed or unexposed portions of the photoresist depending on whether a positive or negative resist is used. Thus, a pattern corresponding to the pattern of the reticle is formed in the photoresist, which may be used as a mask layer to transfer the pattern to an underlying layer.